First, thanks for the help! I got my car back from the shop and I am pleased to say that it's
fixed! It's a wonderful little Benz!
On Monday the shop checked out the car's suspension and and found two things wrong: 1. The wheel bearing needed to be adjusted. 2. The idler arm bushings needed to be replaced. They adjusted the wheel bearing on Monday, but they didn't have the kit so they had to order that. Tuesday, I drove the car and I could tell that it felt better, but the "floating" was still there. After the kit arrived they replaced those as well. That cured the problem. The cost for the bushing kit was around $42.00 with the labour (including the wheel bearing adjustment) was around $93.00.
Again, the problem was in any sort of of crosswind, at speeds in excess of 100 kph the car felt as if it was unstable by being blown left and right.
I hope this helps!